Shengyishe published its September 18 national sulfur benchmark at 7,685.67 yuan per metric tonne on Thursday in the open commodity table.
The print was down 0.24 percent on the day, a modest move after sharper corrections on September 15 and 16 that had already pulled the index below 7,750 yuan.
Month to date the benchmark is down 7.95 percent versus the September 1 opening level of 8,349 yuan per tonne in the same release.
That MTD draw keeps domestic spot well below the record 9,875 yuan per tonne weekly average BC Insight cited for 11 June, when port congestion and import parity still supported extreme highs.
Late August port stocks near 947,000 tonnes in BC Insight's September 18 account add inventory weight even as Hormuz-route import costs stay elevated in SunSirs and SMM reviews.
SMM's week-ending September 18 sulphuric acid weekly review put Shandong elemental sulphur EXW at 7,257 to 7,650 yuan per tonne, averaging 7,453.5 yuan, down 7.2 percent week on week.
The elemental and acid chains are moving together this week, unlike some September sessions where acid lagged sharper benchmark steps.
Middle East FOB sulphur averaged 855 dollars per tonne flat in SMM's table while CFR India was cut to an average near 1,050 dollars per tonne from 1,075 dollars.
QatarEnergy's September monthly contract at 880 dollars per tonne FOB remains far below granular import parity once freight and insurance on risk cargoes are counted.
For Alberta forming plants, a 7,685 yuan domestic print does not by itself collapse Pacific export netbacks when BC Insight firms Vancouver FOB to 1,100 to 1,200 dollars on a confirmed Southern Africa sale the same day.
Canadian sulphur through the Vancouver Fraser Port Authority totalled 3,507,428 metric tonnes in 2025, up 5 percent year on year, and remains the swing Pacific stem when Gulf bulk loadings stay impaired.
Alberta provincial sulfur stocks at 11.66 million tonnes in July 2025 in open AER-derived reporting keep the inventory-draw narrative in place even as Chinese benchmarks correct.
US phosphate stress persists in parallel: UkrAgroConsult on September 18 cited Tampa delivered sulfur above 1,100 dollars per tonne since May and Mosaic running near 50 percent rates in Florida and Louisiana.
Desk read: September 18 Shengyishe is a small down day inside a larger September correction. Treat 7,685.67 yuan as the open national anchor until the next benchmark print, and read MTD minus 7.95 percent as the pace of domestic easing.